docs: def _diffsigma(self, Ep, Egamma):
          """
          Differential cross section
  
          dsigma/dEg = Amax(Tp) * F(Tp,Egamma)
          """
          Tp = Ep - self._m_p
  
          diffsigma = self._Amax(Tp) * self._F(Tp, Egamma)
  
          if self.nuclear_enhancement:
              diffsigma *= self._nuclear_factor(Tp)
  
          return diffsigma